osfmk/ipc/ipc_mqueue.c

63  *	Functions to manipulate IPC message queues.
74 #include <mach/message.h>
98 int ipc_mqueue_rcv;		/* address is event for message arrival */
106  *		Initialize a newly-allocated message queue.
153  *		set message queue.
263 			 * handed the message directly.  Just set it running, and
272 			 * Found a receiver. see if they can handle the message
273 			 * correctly (the message is not too large for them, or
274 			 * they didn't care to be informed that the message was
286 					 * let him go without message
299 			 * This thread is going to take this message,
308 			break;  /* go to next message */
321  *		Wake up receivers waiting in a message queue.
323  *		The message queue is locked.
343  *		Send a message to a message queue.  The message holds a reference
344  *		for the destination port for this message queue in the
348  *		the message and must do something with it.  If successful,
349  *		the message is queued, given to a receiver, or destroyed.
353  *		MACH_MSG_SUCCESS	The message was accepted.
354  *		MACH_SEND_TIMED_OUT	Caller still has message.
355  *		MACH_SEND_INTERRUPTED	Caller still has message.
450  *		Release a message queue reference in the case where we
454  *		The message queue is locked.
455  *		The message corresponding to this reference is off the queue.
483  *		Post a message to a waiting receiver or enqueue it.  If a
485  *		the message queue.
488  *		If we need to queue, our space in the message queue is reserved.
501 	 *	Check for a receiver for the message.
529 		 * handed the message directly.  Just set it running, and
540 		 * If the message is too large or the scatter list is too small
571 		 * and handle its error without getting the message.  We
613 		 * We do not need to go select a message, somebody
621 			 * message. If we indicated that we cared,
624 			 * AND the message anyway.
654  *		Receive a message from a message queue.
672  *		MACH_RCV_TIMED_OUT	No message obtained.
673  *		MACH_RCV_INTERRUPTED	No message obtained.
674  *		MACH_RCV_PORT_DIED	Port/set died; no message.
787 			 * Continue on to handling the message with just
855  *		A receiver discovered that there was a message on the queue
856  *		before he had to block.  Pick the message off the queue and
861  *		There is a message.
863  *		MACH_MSG_SUCCESS	Actually selected a message for ourselves.
879 	 * before pulling the message off the queue.
916  *		Peek at a (non-set) message queue to see if it has a message
918  *		first message in the queue) and return vital info about the
919  *		message.
923  *		Caller holds reference on the message queue.
954 	/* look for the message that would match that seqno */
986  *		Peek at a message queue set to see if it has any ports
991  *		Caller holds reference on the message queue.
1007 	 * peek at the contained port message queues, return as soon as
1008 	 * we spot a message on one of the message queues linked on the
1009 	 * prepost list.  No need to lock each message queue, as only the
1010 	 * head of each queue is checked. If a message wasn't there before
1032  *		Iterate a message queue set to identify the member port
1039  *		Caller holds reference on the message queue.
1080  *		Destroy a (non-set) message queue.
1134  *		Changes a message queue limit; the maximum number
1200  *		Convert a name in a space to a message queue.
1206  *		MACH_MSG_SUCCESS	Found a message queue.